Control theoretic approach to gyro-free inertial navigation systems

In this article, we presented a state-of-the-art review of gyro-free inertial navigation systems (GF-INS) and compared it to the classical INS architecture for six categories. After reviewing the unified GF models, stability analysis showed that the addition of the angular velocity error states into the state-space model results in at least one eigenvalue inside the right half-plane (RHP) diverging the system. In addition, the observable and unobservable subspaces were analytically derived for the GF FA process with velocity measurements. It was shown that regardless of the GF configuration, the observability matrix rank is always 10.